Abstract
Fruit-based beer fermentation introduces additional sugars, organic acids, phenolic compounds, and aroma precursors that can modify yeast metabolism and sensory quality. This study investigates yeast-derived aroma formation during fruit-based beer fermentation. Controlled fermentations were prepared using standard malt wort with selected fruit additions at defined fermentation stages. Yeast growth, sugar consumption, ethanol formation, pH variation, ester production, higher alcohol concentration, aldehyde reduction, organic acid profile, and sensory aroma descriptors were monitored. The results show that fruit-derived sugars increased early fermentation activity, while organic acids influenced yeast stress response and aroma balance. Moderate fruit addition enhanced ester complexity and produced stronger fruity notes without masking malt character. Excessive fruit concentration increased acidity and caused uneven aroma development. The study demonstrates that fruit-based beer quality depends on careful control of fruit addition timing, yeast activity, and fermentation conditions. Overall, the findings support stable production of aromatic fruit beers.